<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="lib/vue.js"></script>
</head>
<body>
<div id="root">
    <button @click.once="num++">{{num}}</button>
</div>
</body>
<script>
	new Vue({
		el: "#root",
        data:{
			num:100
        }
	})
</script>
</html>